Genes downstream of p53 mediating its effect on megakaryopoiesis
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ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE30984 | GEO | 2011/07/27
SECONDARY ACCESSION(S): PRJNA146195
REPOSITORIES: GEO
Similar Datasets
Project description:In order to examine genes whose expression is altered as a result of the knock-down (KD) of p53, we used gene expression microarray analysis based on the CHRF cell line, a human megakaryoblastic cell line, which upon PMA stimulation undergoes polyploidization, and extends proplatelet-like cytoplasmic protrusions combined with apoptosis. The CHRF cell line has been validated in our laboratory as a good model of in vitro megakaryopoiesis by comparison to hematopoietic stem cells undergoing Mk differentiation. As described, we have previously generated stable p53-KD CHRF cell lines by lentiviral delivery of microRNA-adapted-short hairpin sequences targeting p53 as well as a suitable scrambled-control cell line. For the microarray analysis we utilized the 4x44K whole human genome microarrays from Agilent. This analysis compared the p53-KD CHRF cells against the control CHRF cells in the absence of PMA treatment and on days 1, 3, 5 and 7 after PMA treatment (5 time-points). p53-KD and control samples were hybridized against each other (direct comparison). We carried out two biological replicate experiments, i.e., 10 measurements of gene expression for each microarray probe. Probes from which >50% of measurements were missing were discarded and not included in the analysis of differential expression. Differentially expressed genes were identified using the significance analysis of microarrays (SAM) with a false discovery rate (FDR) of less than 5%, as implemented in the MultiExperiment Viewer (MeV) tool.
2011-07-26 | E-GEOD-30984 | biostudies-arrayexpress
Project description:Little is known about the global transcriptional program underlying megakaryocytic (Mk) differentiation, maturation, and apoptosis. Using DNA microarrays and Q-RT-PCR, we examined the transcriptional profile of phorbol-ester-induced Mk differentiation of the megakaryoblastic CHRF-288-11 (CHRF) cell line – a model system for investigating megakaryopoiesis. The goals of this study were to (1) verify the megakaryocytic nature of the CHRF cell line at the transcriptional level, and (2) extract novel insights into the key facets of Mk maturation including polyploidization, proplatelet formation, and apoptosis. Keywords: time course
2006-11-08 | GSE3838 | GEO
Project description:Little is known about the global transcriptional program underlying megakaryocytic (Mk) differentiation, maturation, and apoptosis. Using DNA microarrays and Q-RT-PCR, we examined the transcriptional profile of phorbol-ester-induced Mk differentiation of the megakaryoblastic CHRF-288-11 (CHRF) cell line â a model system for investigating megakaryopoiesis. The goals of this study were to (1) verify the megakaryocytic nature of the CHRF cell line at the transcriptional level, and (2) extract novel insights into the key facets of Mk maturation including polyploidization, proplatelet formation, and apoptosis. Experiment Overall Design: CHRF-288 cells were cultured in the presence of 10 ng/mL phorbol ester (PMA) or equivalent volume of DMSO solvent (0.02%). Unstimulated control cells from time zero (exponentially growing CHRF cells) were also analyzed. For PMA treated legs, only the adherent cells were included in the transcriptional analysis. Two biological replicate experiments were analyzed and approximately one-half of the samples with each experiment were technically replicated. Hybridizations were performed in a reference design with all samples labeled with Cy3 and a reference RNA pool labeled with Cy5.
2008-06-12 | E-GEOD-3838 | biostudies-arrayexpress
Project description:The role of ABCC4, an ATP-binding cassette transporter, in the process of platelet formation, megakaryopoiesis, is unknown. Here, we show that ABCC4 is highly expressed in megakaryocytes (MKs). Mining of public genomic data (ATAC-seq and genome wide chromatin interactions, Hi-C) revealed that key megakaryopoiesis transcription factors (TFs) interacted with ABCC4 regulatory elements and likely accounted for high ABCC4 expression in MKs. Importantly these genomic interactions for ABCC4 ranked higher than for genes with known roles in megakaryopoiesis suggesting a role for ABCC4 in megakaryopoiesis. We then demonstrate that ABCC4 is required for optimal platelet formation as in vitro differentiation of fetal liver derived MKs from Abcc4-/- mice exhibited impaired proplatelet formation and polyploidization, features required for optimal megakaryopoiesis. Likewise, a human megakaryoblastic cell line, MEG-01 showed that acute ABCC4 inhibition markedly suppressed key processes in megakaryopoiesis and that these effects were related to reduced cAMP export and enhanced dissociation of a negative regulator of megakaryopoiesis, protein kinase A (PKA) from ABCC4. PKA activity concomitantly increased after ABCC4 inhibition which was coupled with significantly reduced GATA-1 expression, a TF needed for optimal megakaryopoiesis. Further, ABCC4 protected MKs from 6-mercaptopurine (6-MP) as Abcc4-/- mice show a profound reduction in MKs after 6-MP treatment. In total, our studies show that ABCC4 not only protects the MKs but is also required for maximal platelet production from MKs, suggesting modulation of ABCC4 function might be a potential therapeutic strategy to regulate platelet production.
2024-01-05 | GSE234560 | GEO
Project description:The role of ABCC4, an ATP-binding cassette transporter, in the process of platelet formation, megakaryopoiesis, is unknown. Here, we show that ABCC4 is highly expressed in megakaryocytes (MKs). Mining of public genomic data (ATAC-seq and genome wide chromatin interactions, Hi-C) revealed that key megakaryopoiesis transcription factors (TFs) interacted with ABCC4 regulatory elements and likely accounted for high ABCC4 expression in MKs. Importantly these genomic interactions for ABCC4 ranked higher than for genes with known roles in megakaryopoiesis suggesting a role for ABCC4 in megakaryopoiesis. We then demonstrate that ABCC4 is required for optimal platelet formation as in vitro differentiation of fetal liver derived MKs from Abcc4-/- mice exhibited impaired proplatelet formation and polyploidization, features required for optimal megakaryopoiesis. Likewise, a human megakaryoblastic cell line, MEG-01 showed that acute ABCC4 inhibition markedly suppressed key processes in megakaryopoiesis and that these effects were related to reduced cAMP export and enhanced dissociation of a negative regulator of megakaryopoiesis, protein kinase A (PKA) from ABCC4. PKA activity concomitantly increased after ABCC4 inhibition which was coupled with significantly reduced GATA-1 expression, a TF needed for optimal megakaryopoiesis. Further, ABCC4 protected MKs from 6-mercaptopurine (6-MP) as Abcc4-/- mice show a profound reduction in MKs after 6-MP treatment. In total, our studies show that ABCC4 not only protects the MKs but is also required for maximal platelet production from MKs, suggesting modulation of ABCC4 function might be a potential therapeutic strategy to regulate platelet production.
2024-01-05 | GSE234628 | GEO
Project description:S78454 (Abexinostat, PCI-24781) is a pan histone deacetylase inhibitor (HDACi) that demonstrates efficacy in malignancy treatment. Like other HDACi, this drug induces a profound thrombocytopenia, whose mechanism is partially understood. We have tested its effect at doses reached in patients plasma on in vitro megakaryopoiesis derived from human CD34+ cells. When added at day 0 in culture, S78454 inhibited CFU-MK growth, megakaryocyte (MK) proliferation and differentiation. This effect only required a short incubation period. When added later on (day 8), the compound induced a dose-dependent decrease (up to 10-fold) in proplatelet formation. Decreased proliferation was due to induction of apoptosis and was not related to a defect in TPO/MPL/JAK2 signaling. MK gene profiling revealed a silencing in the expression of DNA repair genes with a marked RAD51 decrease at protein level. Double DNA strand breaks were increased as attested by elevated gH2AX phosphorylation level. Consequently, ATM was phosphorylated leading to p53 stabilization and increased BAX and p21 expression. The use of a p53 shRNA rescued apoptosis, but only partially the defect in proplatelet formation. These results suggest that HDACi induces a thrombocytopenia by a p53 dependent mechanism along MK differentiation and a p53 independent mechanism for proplatelet formation.
2013-06-30 | E-MTAB-1180 | biostudies-arrayexpress
Project description:Megakaryoblastic Leukemia 1 (MKL1) was identified as part of the t(1;22) translocation specific to acute megakaryoblastic leukemia, but nothing is known regarding its role in hematopoiesis. Here we show that overexpression of MKL1 enhances megakaryocytic differentiation of the Human Erythroleukemia cell line (HEL). Microarray analysis reveals that MKL1 promotes expression of megakaryocyte-specific genes such as glycoprotein V (GP5), as well as cytoskeletal and adhesion molecule genes relevant to megakaryocyte differentiation and proplatelet formation. MKL1 is a transcriptional coactivator of Serum Response Factor. In this study, MKL1 also upregulates known SRF targets. Results provide insight into the role of MKL1 in megakaryocytopoiesis.
2008-12-10 | GSE13710 | GEO
Project description:EZH2, the enzymatic component of PRC2, has been identified as a key factor in hematopoiesis. EZH2 loss of function mutations have been found in myeloproliferative neoplasms, more particularly in myelofibrosis, but the precise function of EZH2 in megakaryopoiesis is not fully delineated. Here, we show that EZH2 inhibition by small molecules and shRNA induces MK commitment by accelerating lineage marker acquisition without change in proliferation. Later in differentiation, EZH2 inhibition blocks proliferation and endomitosis and decreases proplatelet formation. EZH2 inhibitors similarly reduce polyploidization and proplatelet formation of JAK2V617F MK. In transcriptome profiling, the defect in proplatelet formation was associated with an aberrant actin cytoskeleton regulation pathway, whereas polyploidization was associated with an inhibition of expression for a set of genes involved in DNA replication and repair, and an upregulation of CDK inhibitors, more particularly CDKN1A and CDKN2D. The knockdown of CDKN1A and/or CDKN2D could partially rescue the percentage of polyploid MKs. However only CDKN1A was regulated by H3K27me3 suggesting that EZH2 controls MK polyploidization through a direct regulation of CDKN1A and indirectly of CDKN2D.
2021-11-02 | E-MTAB-8609 | biostudies-arrayexpress
Project description:EZH2, the enzymatic component of PRC2, has been identified as a key factor in hematopoiesis. EZH2 loss of function mutations have been found in myeloproliferative neoplasms, more particularly in myelofibrosis, but the precise function of EZH2 in megakaryopoiesis is not fully delineated. Here, we show that EZH2 inhibition by small molecules and shRNA induces MK commitment by accelerating lineage marker acquisition without change in proliferation. Later in differentiation, EZH2 inhibition blocks proliferation and endomitosis and decreases proplatelet formation. EZH2 inhibitors similarly reduce polyploidization and proplatelet formation of JAK2V617F MK. In transcriptome profiling, the defect in proplatelet formation was associated with an aberrant actin cytoskeleton regulation pathway, whereas polyploidization was associated with an inhibition of expression for a set of genes involved in DNA replication and repair, and an upregulation of CDK inhibitors, more particularly CDKN1A and CDKN2D. The knockdown of CDKN1A and/or CDKN2D could partially rescue the percentage of polyploid MKs. However only CDKN1A was regulated by H3K27me3 suggesting that EZH2 controls MK polyploidization through a direct regulation of CDKN1A and indirectly of CDKN2D.
2021-03-31 | E-MTAB-8611 | biostudies-arrayexpress
Project description:EZH2, the enzymatic component of PRC2, has been identified as a key factor in hematopoiesis. EZH2 loss of function mutations have been found in myeloproliferative neoplasms, more particularly in myelofibrosis, but the precise function of EZH2 in megakaryopoiesis is not fully delineated. Here, we show that EZH2 inhibition by small molecules and shRNA induces MK commitment by accelerating lineage marker acquisition without change in proliferation. Later in differentiation, EZH2 inhibition blocks proliferation and endomitosis and decreases proplatelet formation. EZH2 inhibitors similarly reduce polyploidization and proplatelet formation of JAK2V617F MK. In transcriptome profiling, the defect in proplatelet formation was associated with an aberrant actin cytoskeleton regulation pathway, whereas polyploidization was associated with an inhibition of expression for a set of genes involved in DNA replication and repair, and an upregulation of CDK inhibitors, more particularly CDKN1A and CDKN2D. The knockdown of CDKN1A and/or CDKN2D could partially rescue the percentage of polyploid MKs. However only CDKN1A was regulated by H3K27me3 suggesting that EZH2 controls MK polyploidization through a direct regulation of CDKN1A and indirectly of CDKN2D.
2021-11-02 | E-MTAB-8610 | biostudies-arrayexpress